Financial Modeling Prep MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions the API source and data types but omits critical behavioral details: whether this requires authentication, rate limits, pagination behavior, error conditions, or what format the data returns. 'Retrieve' implies read-only, but this isn't explicitly stated.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is efficiently structured in two sentences with zero waste. The first sentence states the core purpose, and the second adds context about data types and analysis utility. However, it could be more front-loaded with critical behavioral information given the lack of annotations.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a data retrieval tool with no annotations and no output schema, the description is incomplete. It doesn't address authentication requirements, rate limits, error handling, response format, or data freshness - all critical for an AI agent to use this tool effectively. The 100% schema coverage helps, but doesn't compensate for missing behavioral context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents all three parameters. The description adds no additional parameter semantics beyond what's in the schema - it doesn't explain symbol conventions beyond the example, date format constraints, or default behaviors for optional parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Retrieve end-of-day historical prices for stock indexes' with specific resources (stock indexes) and data types (date, price, volume). It distinguishes from siblings like 'getHistoricalIndexFullChart' by specifying 'LightChart' format, but doesn't explicitly contrast with other historical data tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose this over 'getHistoricalIndexFullChart', 'getIndex1MinuteData', or other historical data tools, nor does it specify prerequisites or appropriate contexts for use.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.